Windows that are used in the construction of buildings often are of the type comprising a movable panel of glass known as a “sash”. Common window types include single or double hung sash windows, sliding sash, awning sash and casement sash windows wherein the frame of the window and the frame of the sash containing the window glass is made of aluminium, timber, steel or PVC. Such windows are often used in the construction of residential dwellings in single or multi-level residential buildings, apartment buildings, commercial and industrial structures and the like. Single-hung sash and double-hung sash windows include at least one window sash that is movable in a vertical direction and sliding sash windows have at least one sash that is movable in a horizontal direction. Awning sash and casement windows include at least one window sash that pivots relative to a window frame. A problem with such windows is that children can and do fall out of them. Where such windows are employed in the construction of dwellings that are elevated above ground level, such as in multi story residential dwellings, apartment buildings and the like, a child falling out of such a window can suffer serious injury or death.
A solution to the problem of children falling out of windows is to restrict the extent to which the window can be opened. By restricting the extent to which a window can be opened children can be prevented from falling out of a window whilst still enabling windows to be opened to provide for ventilation. Existing window restrictors involve simply preventing a window sash from being opened beyond a certain amount but do not maintain the window open or closed. Furthermore, such restrictors may not be resistant to operation by a child and, therefore, may not prevent a child from deactivating the restrictor.
Other means of restricting the extent to which a window can be opened include window locks having a key operated lock that is operable to lock a bolt which passes through the frame of the window sash and either the frame of the window or of another window sash to thereby lock the sash window in a predetermined open position. A problem with such window locks is that as they include a key operated lock thus rendering the window lock relatively expensive to manufacture. Furthermore, such window locks require the use of a key to operate the lock which is problematic because such keys can and do go missing and it is not recommended to leave the key in the lock as the lock can then be operated by a child which is not desirable. If the key for a window lock is misplaced then the lock may be rendered useless and need to be removed from the window in order to enable the window to be opened and closed. Furthermore, in the event of a fire, it may not be possible for a person within the dwelling to reach the key to unlock the window lock and exit the dwelling. It may also not be possible for a person outside the dwelling, such as fire or emergency response personnel, to unlock the window lock and enter the dwelling without breaking the window and risking injury associated with entering or exiting a window containing broken glass.
Accordingly, a need exists for a means of restraining a window sash in an open position that is small enough to prevent a child from falling out of the window yet which is secure enough to prevent the child from further opening and falling out of the window. There also exists a need to provide a means of restraining a sash window in an open position or a closed position that is relatively inexpensive and alleviates problems associated with key operated window locks.